Prior solutions to determining vehicle attitude using GPS have required two or more antenna/receiver combinations. Small devices such as micro-unmanned aerial vehicles (UAV's), personal navigators, cellular telephones and other small vehicles lack the dimensions required to host traditional multiple antenna attitude determination systems.
In addition to attitude determination, multiple antenna systems have been used to detect spoofing by computing the direction of the incoming satellite navigation signal.
In safety critical applications, such as Positive Train Control (PTC) systems, the attitude of the locomotive on track is critical to locate the train. Attitude computed directly from each antenna of a multiple antenna system creates an additional input to check correctness of other calculations.